525efi - fuel/water separator
#1
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Joined: Jan 2005
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From: Canyon Lake, TX
Curious, while the manual does not mention to do so, when changing, do you guys fill the small spin on fuel/water separator with fresh fuel before spinning it on? My thought is to do so to minimize air or gap of fuel. Maybe the fuel pump pushes enough through when you turn the key on such that this isnt necessary? Just looking for comment from you experienced guys. Thanks!
#2
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Joined: Jul 2011
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From: Ft. Worth TX
100 percent YES fill with fresh fuel and coat the oring with a good motor oil. Do not over tighten.
Merc even has a service bulletin about filling the water fuel sep filter with fuel as well. Some times you can get a no start with a dry filter install.
Merc even has a service bulletin about filling the water fuel sep filter with fuel as well. Some times you can get a no start with a dry filter install.
#4
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From: On A Dirt Floor
#6
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From: Canyon Lake, TX
Well, finally got the new fuel/water separators on. Instructions on the box even say to fill filter with fresh fuel, so all good there. I guess my question is, how does one know I did good by changing them? I will say, the color of the fuel that I poured out of the old ones (both engines) was on the transparent green side, nothing like the clear fresh fuel that I put in the new ones. Fired up the engines, ran fine, idle psi was in the 39-42 range....
Does contaminated fuel with water in the separator turn that greenish color? almost like a light green coolant color. Just curious.
Does contaminated fuel with water in the separator turn that greenish color? almost like a light green coolant color. Just curious.
#7
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From: Ft. Worth TX
2 stroke oil mix and or fuel stabil will turn gas green tint. Old stale bad gas turns like Ice tea color and smells like old paint varnish. Water in the fuel -- the water goes to the bottom because the specific gravity is higher than fuel. Meaning water is heavier than fuel.
Is this boat new to you ? if not who winterized it or any storage lay up ?
Is this boat new to you ? if not who winterized it or any storage lay up ?
#8
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From: Canyon Lake, TX
I got the boat to TX Aug 2014, 99hrs on her from original owner. Dealer serviced it before it left Chicago to TX (presume they changed them as part of 100hr service that was performed). Garage kept in TX, so dont winterize, but do start it 1x/mo in winter. Been my "winterize" formula in TX for all my boating years. Yes I do use Marine Stabil. That may have changed the fuel color. As for seeing water, I really cant say I did. However, at least I know for sure now that they have been changed!
Last edited by imartin; 08-13-2018 at 04:21 PM.



